Medicine and Health Sciences Commons^™

Infectious Disease And The Diversification Of The Human Genome, Jessica F. Brinkworth

Human Biology Open Access Pre-Prints

The human immune system is under great pathogen-mediated selective pressure. A combination of divergent infectious disease pathogenesis across human populations, and the overrepresentation of “immune genes” in genomic regions with signatures of positive selection suggests that pathogens have significantly altered the human genome. However, important features of the human immune system can confound searches for and interpretations of signatures of pathogen-mediated evolution. Immune system redundancy, immune gene pleiotropy, host ability to acquire immunity and alter the immune repertoire of their offspring through “priming”, and host microbiome complicate evolutionary interpretations of host- pathogen interactions. The overall promiscuity and sensitivity of the …

Interaction Of Alu Polymorphisms And Novel Measures Of Discrimination In Association With Blood Pressure In African Americans Living In Tallahassee, Alexis C. Boulter, Jackyn Quinlan, Aida T. Miró-Herrans, Laurel N. Pearson, Nubiana L. Todd, Clarence C. Gravlee, Connie J. Mulligan

Human Biology Open Access Pre-Prints

African Americans are 40% more likely to be afflicted with hypertension in comparison to non-Hispanic, white Americans, resulting in a 30% higher instance of mortality due to cardiovascular disease. There is debate about the relative contributions of genetic and sociocultural risk factors to the racial disparity in hypertension.

We assayed three Alu insertion polymorphisms located in the angiotensin-1-converting enzyme (ACE), tissue plasminogen activator (PLAT), and with no-lysine kinase 1 (WNK1) genes. We also estimated West African genetic ancestry and developed novel measures of perceived discrimination to create a biocultural model of blood pressure among …

Evolution And Otitis Media: A Review, And A Model To Explain High Prevalence In Indigenous Populations, Mahmood F. Bhutta

Human Biology Open Access Pre-Prints

Inflammation of the middle ear (otitis media) comprises a group of disorders that are highly prevalent in childhood, and indeed are amongst the most common disorders of childhood. Otitis media is also heritable, and has effects on fecundity. This means that otitis media is subject to evolution, yet the evolutionary selection forces that may determine susceptibility to otitis media have never been adequately explored.

Here I undertake a critical analysis of evolutionary forces that may determine susceptibility to middle ear inflammation. These forces include those determining function of the middle ear, those affecting host immunity, and those affecting colonization by, …

Comparing Partial Least Square Approaches In Gene-Or Region-Based Association Study For Multiple Quantitative Phenotypes, Zhongshang Yuan, Xiaoshuai Zhang, Fangyu Li, Jinghua Zhao, Fuzhong Xue

Human Biology Open Access Pre-Prints

On thinking quantitatively of complex diseases, there are at least three statistical strategies for association study: single SNP on single trait, gene-or region (with multiple SNPs) on single trait and on multiple traits. The third of which is the most general in dissecting the genetic mechanism underlying complex diseases underpinning multiple quantitative traits. Gene-or region association methods based on partial least square (PLS) approaches have been shown to have apparent power advantage. However, few attempts are developed for multiple quantitative phenotypes or traits underlying a condition or disease, and the performance of various PLS approaches used in association study for …

Pedigree Structure And Kinship Measurements Of A Mid-Michigan Community: A New North American Population Isolate Identified, Joseph D. Bonner, Rachel Fisher, James Klein, Qing Lu, Ellen Wilch, Karen H. Friderici, Jill L. Elfenbein, Debra L. Schutte, Brian C. Schutte

Human Biology Open Access Pre-Prints

Previous studies identified a cluster of individuals with an autosomal recessive form of deafness that resides in a small region of mid-Michigan. We hypothesized that affected members from this community descend from a defined founder population. Using public records and personal interviews, we constructed a genealogical database that includes the affected individuals and their extended families as descendants of 461 settlers who emigrated from the Eifel region of Germany between 1836 and 1875. The genealogical database represents a 13-generation pedigree that includes 27,747 descendants of these settlers. Among these descendants, 13,784 are presumed living. Many of the extant descendants reside …

Celiac Disease As A Model For The Evolution Of Multifactorial Disease In Humans, Aaron Sams, John Hawks

Human Biology Open Access Pre-Prints

Celiac disease (CD) is a multifactorial chronic inflammatory condition that results in injury of the mucosal lining of the small intestine upon ingestion of wheat gluten and related proteins from barley and rye. Although the exact mechanisms leading to CD are not fully understood, the genetic basis of CD has been relatively well characterized. In this review we briefly review the history of discovery, clinical presentation, pathophysiology, and current understanding of the genetics underlying CD risk. Then, we discuss what is known about the current distribution and evolutionary history of genes underlying CD risk in light of other evolutionary models …

Lactase Persistence Variants In Arabia And In The African Arabs, Edita Priehodova, Abdelhay Abdelsawy, Evelyne Heyer, Viktor Cerny

Human Biology Open Access Pre-Prints

Lactase persistence (LP), the state enabling the digestion of milk sugar in adulthood occurs only in some human populations. The convergent and independent origin of this physiological ability in Europe and Africa is linked with animal domestication that had either started in both places independently or had spread from the Near East by acculturation. However, it has recently been shown that at least in its southern parts, the population of Arabia not only has a different LP-associated mutation profile than the rest of Africa and Europe but had also experienced an independent demographic expansion occurring before the Neolithic around the …

The -9/+9 Polymorphism Of The Bradykinin Receptor Beta 2 Gene And Athlete Status: A Study Involving Two European Cohorts., Marek Sawczuk, Yevgeniya I. Timshina, Irina V. Astratenkova, Agnieszka Maciejewska-Karłowska, Agata Leońska-Duniec, Krzysztof Ficek, Leysan J. Mustafina, Paweł Cięszczyk, Tomasz Klocek, Ildus I. Ahmetov

Human Biology Open Access Pre-Prints

Background: Previous studies concerning the relevance of the BDKRB2 gene polymorphisms revealed that the absence (–9 allele) of a 9 base pair sequence in exon 1 of the BDKRB2 gene is correlated with higher skeletal muscle metabolic efficiency, glucose uptake during exercise, as well as endurance athletic performance. Aim: The aim of the study was to investigate the association between the BDKRB2 -9/+9 polymorphism and elite athletic status in two cohorts of east-European athletes. Therefore, we examined the genotype distribution of the BDKRB2 9/+9 polymorphic site in a group of Polish athletes and confirmed the results obtained in a replication …

How Studies Of Human Sex Ratios At Birth May Lead To The Understanding Of Several Forms Of Pathology, William H. James

Human Biology Open Access Pre-Prints

This paper deals with the problem of the causes of the variation of sex ratio (proportion male) at birth. This problem is common to a number of areas in biology and medicine e.g. obstetrics, neurology/psychiatry, parasitology, virology, oncology and teratology. It is established that there are significantly biased, but unexplained, sex ratios in each of these fields. Yet workers in them (with the possible exception of virology) have regarded the problem as a minor loose end, irrelevant to the field’s major problems. However, as far as I know, no-one has previously noted that unexplained biased sex ratios occur, and thus …

Resource Availability, Mortality And Fertility: A Path Analytic Approach To Global Life History Variation, Mark A. Caudell, Robert J. Quinlan

Human Biology Open Access Pre-Prints

Humans exhibit considerable diversity in timing and rate of reproduction. Life history theory suggests that ecological cues of resource richness and survival probabilities shape human phenotypes across populations. Populations experiencing high extrinsic mortality due to uncertainty in resources should exhibit faster life histories. Here we use a path analytic approach informed by life history theory to model the multiple pathways between resources, mortality rates, and reproductive behavior in 191 countries. Resources that account for the most variance in population mortality rates are predicted to explain the most variance in total fertility rates. Results indicate that resources (e.g., calories, sanitation, education, …

Association Among Obesity-Related Anthropometric Phenotypes: Analyzing Genetic And Environmental Contribution, Aline Jelenkovic, Esther Rebato

Human Biology Open Access Pre-Prints

Obesity has become a public health and policy problem in many parts of the world. Epidemiological and population studies in this field are usually based on different anthropometric measures, however, common genetic and environmental factors between these phenotypes have been scarcely studied. The objective of this work is to assess the strength of these factors on the covariation among a large set of obesity-related traits. The subject group consisted of 533 nuclear families living in the Greater Bilbao (Spain), and included 1702 individuals aged 2-61 years. Detailed anthropometric measurements (stature, breadths, circumferences and skinfolds) were carried out in each subject. …

Book Review: Reproduction And Adaptation: Topics In Human Reproductive Ecology, Geoff Kushnick Phd

Human Biology Open Access Pre-Prints

Reproduction and Adaptation: Topics in Human Reproductive Ecology. Edited by C.G. Mascie-Taylor and Lyliane Rosetta. Cambridge Studies in Biological and Evolutionary Anthropology, Vol. 59. Cambridge: Cambridge University Press. 2011. 282 pp. $99.00 (hardback). ISBN 978-0-521-50963-3.

Gestation Length, Mode Of Delivery And Neonatal Line Thickness Variation, CléMent Zanolli, Luca Bondioli, Franz Manni, Paola Rossi, Roberto Macchiarelli

Human Biology Open Access Pre-Prints

The transition from an intra- to extra-uterine environment leaves its mark in deciduous teeth (and first permanent molars) as an accentuated enamel incremental ring called the neonatal line (NL). This prominent microfeature separates the enamel formed during intrauterine life from that formed after leaving the womb. However, while the physical structure of this scar is well known, the bases of its formation are still a matter of investigation. In particular, besides the influence of the birth-related abrupt environmental and dietary changes and the role played by physiological factors such as hypocalcaemia, it has been suggested a direct relationship between NL …